1. Field of the Invention
The present invention relates to an image processing technology, and it particularly relates to an image decoding and image coding technology for detecting scene changes in moving pictures.
2. Description of the Related Art
In the reproduction of moving images, the detection of a change in the scene is called scene change detection.
Normally, the scene change detection is used to efficiently carry out an index search job by detecting a desired scene at a reproducing apparatus or an editing apparatus. Scene change detection techniques normally utilize information on any change that exists between image frames. The known techniques include use of the correlation coefficients applicable between image frames or use of the difference between image frames by statistically processing the pixel values contained in the image frames.
In these conventional techniques, a scene change is normally detected by comparing intensity components of the pixel values of image frames before or after the presently displayed image.
A scene change in moving images compressed by a technique like MPEG (Moving Picture Experts Group) is detected by a processing, such as checking on the above-described correlation coefficient for image data obtained by completely decoding the coded image once. The scene change detection by this technique, therefore, requires large memory area and much computation. Thus, there is room for improvement in detection efficiency.